DNA: The Genetic Material Section 1 Molecular Genetics DNA: The Genetic Material DNA Structure Nucleotides Consist of a five-carbon sugar, a phosphate group, and a nitrogenous base
two outside strands consist of alternating deoxyribose and phosphate Section 1 Molecular Genetics DNA: The Genetic Material Watson and Crick Built a model of the double helix that conformed to the others’ research two outside strands consist of alternating deoxyribose and phosphate cytosine and guanine bases pair to each other by three hydrogen bonds thymine and adenine bases pair to each other by two hydrogen bonds
DNA: The Genetic Material Section 1 Molecular Genetics DNA: The Genetic Material Orientation
DNA often is compared to a twisted ladder. Section 1 Molecular Genetics DNA: The Genetic Material DNA Structure DNA often is compared to a twisted ladder. Rails of the ladder are represented by the alternating deoxyribose and phosphate. The pairs of bases (cytosine–guanine or thymine–adenine) form the steps.
DNA: The Genetic Material Section 1 Molecular Genetics DNA: The Genetic Material Chromosome Structure
Transcription Translation Section 3 Molecular Genetics DNA, RNA, and Protein Central Dogma DNA RNA Proteins Transcription Translation Replication
Semiconservative Replication Section 2 Molecular Genetics Replication of DNA Semiconservative Replication Parental strands of DNA separate, serve as templates, and produce DNA molecules that have one strand of parental DNA and one strand of new DNA.
Section 2 Molecular Genetics Replication of DNA Base pairing
Section 2 Molecular Genetics Replication of DNA Base pairing
Contains the sugar ribose and the base uracil instead of thymine Section 3 Molecular Genetics DNA, RNA, and Protein Central Dogma RNA Contains the sugar ribose and the base uracil instead of thymine Usually is single stranded
Associates with proteins to form ribosomes in the cytoplasm Section 3 Molecular Genetics DNA, RNA, and Protein Messenger RNA (mRNA) Long strands of RNA nucleotides that are formed complementary to one strand of DNA Ribosomal RNA (rRNA) Associates with proteins to form ribosomes in the cytoplasm Transfer RNA (tRNA) Smaller segments of RNA nucleotides that transport amino acids to the ribosome
Section 3 Molecular Genetics DNA, RNA, and Protein
DNA is unzipped in the nucleus and RNA Section 3 Molecular Genetics DNA, RNA, and Protein Transcription Through transcription, the DNA code is transferred to mRNA in the nucleus. DNA is unzipped in the nucleus and RNA polymerase binds to a specific section where an mRNA will be synthesized.
The three-base code in DNA or mRNA is called a codon. Section 3 Molecular Genetics DNA, RNA, and Protein The Code Experiments during the 1960s demonstrated that the DNA code was a three-base code. The three-base code in DNA or mRNA is called a codon.
Steps in Translation 1 – Initiation 2 – Elongation 3 – Termination Section 3 Molecular Genetics DNA, RNA, and Protein Steps in Translation 1 – Initiation 2 – Elongation 3 – Termination
Section 3 Molecular Genetics DNA, RNA, and Protein
Section 3 Molecular Genetics DNA, RNA, and Protein
Each anticodon is complementary to a codon on the mRNA. Section 3 Molecular Genetics DNA, RNA, and Protein Translation In translation, tRNA molecules act as the interpreters of the mRNA codon sequence. At the middle of the folded strand, there is a three-base coding sequence called the anticodon. Each anticodon is complementary to a codon on the mRNA.
Section 3 Molecular Genetics
Section 3 Molecular Genetics
A permanent change that occurs in a cell’s DNA is called a mutation. Section 4 Molecular Genetics Gene Regulation and Mutation Mutations A permanent change that occurs in a cell’s DNA is called a mutation. Types of mutations Point mutation Insertion Deletion
Can occur spontaneously Section 4 Molecular Genetics Gene Regulation and Mutation Causes of Mutation Can occur spontaneously Chemicals and radiation also can damage DNA. High-energy forms of radiation, such as X rays and gamma rays, are highly mutagenic.
Body-cell v. Sex-cell Mutation Section 4 Molecular Genetics Gene Regulation and Mutation Body-cell v. Sex-cell Mutation Somatic cell mutations are not passed on to the next generation. Mutations that occur in sex cells are passed on to the organism’s offspring and will be present in every cell of the offspring.